Former US President Bill Clinton was admitted to a New York hospital on Friday for heart bypass surgery, a statement from his office said.‘‘Former President Bill Clinton is being admitted into New York Presbyterian Hospital today and is scheduled to have bypass surgery,’’ the statement said. No time frame for the surgery was given.The 58-year-old Clinton, a Democrat who served two terms from 1993 to 2001, had gone to Northern Westchester Hospital on Thursday afternoon after experiencing mild chest pain and shortness of breath, his office said.Although initial testing was normal, he spent the night at home in nearby Chappaqua, New York. After additional testing on Friday morning at Westchester Medical Center, doctors advised Clinton should undergo bypass surgery, it said.Clinton’s wife, US Senator Hillary Rodham Clinton, and daughter Chelsea were to be with him for the operation.Before heading back to Manhattan, Hillary said doctors advised her husband to do the surgery ‘‘as soon as he could’’. ABC News reported Clinton was found to have multiple lesions and other TV reports said he would undergo a quadruple bypass. CNN quoted a source close to Clinton as saying the surgery could take place as early as Saturday.Clinton, the 42nd US President, promised at the Democratic National Convention in July to be a ‘‘foot soldier’’ in Democratic presidential nominee John Kerry’s race against Republican President George W. Bush. He received a rousing welcome from delegates after being introduced by his wife, a Democrat representing New York. Kerry, campaigning in Ohio, sent Clinton ‘‘our best wishes, our prayers, our thoughts’’ and asked supporters to give Clinton a cheer he would hear ‘‘all the way to New York’’.In Wisconsin, President Bush said: ‘‘We send him our best wishes for a swift and speedy recovery.’’ White House spokeswoman Claire Buchan said Bush was informed about Clinton’s condition while on Air Force One.